Umarex HDB68 CO2 side mount function No Leaks :) (Restricted with empty 12g co2 in the chamber) 

, this test i stuck an empty co2 12g in the chamber to see the difs, hpa it reduces the power by up to 60% this is good on the oring in the valve and will give you more shots with co2, later ill test the double mount co2 build, i dont have fittings for each marker so i have to undo and re tape them all its a pain in the arse lol but ill get er did :) if you use an 88g in this set up you can expect 60-70 joules depending on temperatures